Introduce LiteralsArray to hide it's implementation.

src/runtime/runtime.h

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef V8_RUNTIME_RUNTIME_H_
 #define V8_RUNTIME_RUNTIME_H_
 
 #include "src/allocation.h"
 #include "src/objects.h"
 #include "src/unicode.h"
@@ skipping 1194 matching lines @@
     ARRAY_ID_FIRST = ARRAY_ID_UINT8,
     ARRAY_ID_LAST = ARRAY_ID_UINT8_CLAMPED
   };
 
   static void ArrayIdToTypeAndSize(int array_id, ExternalArrayType* type,
                                    ElementsKind* fixed_elements_kind,
                                    size_t* element_size);
 
   // Used in runtime.cc and hydrogen's VisitArrayLiteral.
   MUST_USE_RESULT static MaybeHandle<Object> CreateArrayLiteralBoilerplate(
-      Isolate* isolate, Handle<FixedArray> literals,
+      Isolate* isolate, Handle<LiteralsArray> literals,
       Handle<FixedArray> elements, bool is_strong);
 
   static MaybeHandle<JSArray> GetInternalProperties(Isolate* isolate,
                                                     Handle<Object>);
 
   // Find the arguments of the JavaScript function invocation that called
   // into C++ code. Collect these in a newly allocated array of handles
   // (possibly prefixed by a number of empty handles).
   // TODO(mstarzinger): Temporary workaround until this is only used by the
   // %_Arguments and %_ArgumentsLength intrinsics. Make this function local to
@@ skipping 13 matching lines @@
 
 class DeclareGlobalsEvalFlag : public BitField<bool, 0, 1> {};
 class DeclareGlobalsNativeFlag : public BitField<bool, 1, 1> {};
 STATIC_ASSERT(LANGUAGE_END == 3);
 class DeclareGlobalsLanguageMode : public BitField<LanguageMode, 2, 2> {};
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_RUNTIME_RUNTIME_H_